1. Field of the Invention
This invention consists of an electrical resistance tester, specifically, a dual voltage device for the detection of electrical resistance in the range of 0 ohms to 3000 megohms. This device can be powered by either 110 volt alternating current or 12 volt direct current. The test voltages at the test probes are 12 volts direct current for the detection of relatively small resistance and 500 volts direct current for the detection of high resistance.
2. Description of prior art
Devices for the testing of electrical resistance already patented include:
U.S. Pat. No. 4,445,084 Hubert L. Washington Apr. 24, 1984 PA0 U.S. Pat. No. 4,117,397 Isao Fukao-Kimio Monma Sep. 26, 1978 PA0 U.S. Pat. No. 3,934,195 Val Henery Shires Jan. 20, 1976 PA0 U.S. Pat. No. 4,434,401 Robert A. York Feb. 28, 1984 PA0 U.S. Pat. No. 4,140,964 Carol Eubank-Carroll Hayes-Noble Wickliff Feb. 20, 1979
Of the devices already patented only the first one of the above list provides both high and low voltage test modes. It relies on the component being tested to provide the necessary voltage to operate the indicating means. If the component is in the de-energized state no reading can be taken. The others are designed primarily for high resistance detection. The HIGH OR LOW ELECTRICAL RESISTANCE TESTER overcomes these problems by supplying its own operating power and the high voltage test mode incorporated into this tester in which approximately 500 volts D.C. is applied to the component being tested through a neon light and a resistor is safe and unique.